Irving m



@ninth tetes sttnt @Him lR-VlNG M. SCOTT AND WILLIAM ROBERTS ECKART, OF SAN FRANCISCO, CALIFORNIA'.

Letters Patent No. 66,046,6Zated Jime 25, 1867.

IMPROVEMENT IN GUT-OFP VALVES.

TO ALL WHOM IT MAY CONCERN:

Be it known that we, Invnve M. Scorr and WILLIAM R. EcKAn'r, of San Francisco city, San Francisco county, State of California, have invented certain new and useful improvements in i Steam Engines g and we do hereby declare the following description and accompanying drawings are sufficient to enable any person skilled in the art or science to which it most nearly appertains to make and use our said invention without further invention or experiment.

The nature of our invention is to provide an improved seltadjusting cut-oit` for stationary engines, so designed and constructed as to admit'of a slide-valve being used for admitting steam to and from the cylinder of -a steam engine. This end is'aceomplished by constructing an engine in the ordinary manner with a main valve, to admit the steam to :1nd discharge it from the cylinder. Upon the back of `this valve are two eut-off plates, having one opening in each. Through these plates, and parallel with the valve-face, passes arod, having eut upon it one right and one left-hand screw working in corresponding nuts, which are fast to the cut-oil` plates or movable partitions. This rod, it' turned in one direction, moves the plates nearer together, and when turned in the opposite direction, separates them. This 'screw receives its motion from the governor. On the hack of the cut-ol` plates works the cnt-off valve. This valve has a constant travel or throw. The motion of this valve is opposite or nearly opposite to .that of the piston of the engine. The cutting o of the steam takes place byV the cut-od' valve coming in contact and passing over the outer edge of the eut-oit` plates. If the cut-oit plates are moved close together, steam will be eut otl sooner; ii' separated it will be cut oii later. The position ofthe cut-off plates is entirely regulated by the engine. i

To more fully explain l'our invention, reference is had to the accompanying drawing and letters marked thereon, in which- Figure 1 is a side elevation, with our invention attached.

Figure 2, a plan.

Figure 3, an end view.

'Figure 4, side` view of steam-chest, with cover o.

Figure 5 is a transverse section of steam-chest, cut-oi` plates, valves, and part of steam-cylinder.

Similar letters of indicate like parts in each of the figures. i

A is the steam-,cylinder of the engine, with the steam-chest B. a a are the induction ports, and In is the exhaust port. .c is the main valve, which is moved by a rod from the shaft in any suitable manner. This valve has passing through it two steam ports, ai a2, and has in it two exhaust ports, t and b. On the `back of the main valve are two cut-ntf plates, or movable partitions, n n', each of which has an opening, o, 'through which to admit steam. Passing through 'these cut-o platesifsa rod, d. Upon this rod is cut a-right and left-hand screw, Working in the nuts d Vand d', which are fast to the cut-0H' plates n and An. It this rod is turned in one direction, the plates 'n and 'It' are brought closer together; if turned in the opposite direction they will he separated. The eut-oii` valve C is placed on the back of these two plates, and is moved by the engine-shaft in an opposite direction, or nearly so, to that of the piston of the engine. The rod d, which operates the plates n and n', passes through a stuing-box, e, at the end of the steam-chest, and has Afast onits outer end a gear-wheel, g. In connection with this wheel works the wheel z', having a; hub upon it, which serves to keep itin position. Through the centre ofthe wheel t', and its hub, is out a feather-way. In the huh is the end of a spindle or shaft, h, iig. 4, havingv a feather in its lower end, which works in the feather-way in the wheel e'. On the upper end of the spindle zis fast a wheel, lc. Between the wheels e' and c, cut upon the spindle la, is a screw, J, working in a nut 4or screw, j, cut or fast in the plate. At right angles to the 'wheel c is a dummy or change-wheel, m, whose teeth engage in c and o. o is awheel having a. hub on its upper side, which serves to keep it in position. On its under side are fast the projecting pins or lugs au, similar to the lugs r 1', fast on the wheel lc. The three wheels k, m, and o are heldin position by means oi' the yoke p, whose end embracesthe hub on the upper face or back of the wheel o its middle carries the wheel m, and its lower end rests loosely upon the lspindle @ji-List under the wheel lc. Passing through the wheel o loosely, and its hub, is the governor-spindle D, havingbfast upon it, between the wheels c and o, a clutch, s a. The governor-spindle D is moved -verticall'yup or dow-n,

depending upon the speed of the engine, at the same time having a rotary motion. When steam is allowed to enter the steam-chest, after everything is arranged, the cnt-oil` plates n and n will have been so widely separated that the cnt-oli` valve C will not cut oil' the steam from the main valve until the stroke of the piston is nearly or quite completed, the main valve allowing all the steam it receives through the openings v v in the cutoff plates to pass into the cylinder. As the engine attains a greater speed the governor-balls separate, causing the clutehs s to engage in the lugs t t, on the Wheel lc, communicating a rotary motion (in the direction that the governor-'spindle D is revolving) to the wheel lc, spindle h, and wheel tf; the wheelz' always being in contact with the wheel g, fast on tlie rod d, which rod, through the motion it receives, brings the plates n anda closer together, thereby allowing the cnt-oil' valve C to cut o" the communicatiod to the ports a a? through the passage v v, in the cut-oli plates u and n sooner. When the engine has attained the speed for which4 it was designed, the clutch s s travels midway between the points of the lugs u 1t and t't, allowing the wheels o and c to remain at rest. It' the speed of the engine is decreased below its regular speed, the governoimcauscs the clutch e s to engage in the pins u u, upon the wheel o, causing that wheel to engage or communicate, through the intervention of the wheel m, a rotary motion to the wheel c, spindle h', and wheel z', in an opposite direction to that in which the governor-spindle is revolving, causing the rodci. to revolvein an opposite direction to its former motion, thereby separating the plates n and n', allowing the steamv to follow further in the stroke. To prevent the plates n and/n. from being drawn too near together, or spread too far apart, and also to regulate the action of the governor 'upon the pins 'it u and t t, as well as to allow the governor-rod D to communicate to the rod d, as before described, exactly or nearly the same number of 4revolutions that the governor-rod D is making, the screw J upon the spindle 7L is used, when the governor brings the clutch s sin contact with the lugs on the wheel 7c and yoke in, the yoke carrying with it the wheels m and o. If the balls of the governor should take the extreme position allowed them, shown in the greatest outward position in gs. 1,2, 3, the screw .l will have lowered the wheel 7c until the clutch s s can no longer engage with the lugs t t, the cnt-oil plates n n' will have been moved close enough together to have cut oil` all the steam, or nearly all, and cannot be moved any nearer by the governor. If the governor-balls should lower, the clutch s s will engage with the lugs u u, which will move the screw J in the opposite direction', which will raise the yokep and wheels k m o, and at the same time spreading the plates apart, and admitting more steam, until the governor-balls have lowered as far as possible, when the lugs u u will have been moved by the screw J out of contact with the clutch s s; then the cuto plates will have been moved apart to their extreme position, as' shown in figs. Land 5, admitting full, or nearly full, steam to the engine, through the ports no, a3 ft2, and a a. If the wheels k, m, and' o were-prevented from moving vertically up and down, when the clutch s s engaged with the lugs t (,the governor would keep moving the cutol plates nearer together, and cutting oft' steam shorter, until the engine had reduced its speed enough to allow the weight of the ball to overcome the friction between the clutch s s and lugs t t, which would be very great if the rod d communicated a quick motion to the cut-oil' plates 7i n. By using the screw J to raise or lower the wheels 7c, m, and o, if the clutch s s engages with the lugs t t or u u, the friction is overcome, andthe lugs t t or u u are moved out of contact with the clutch s s, by means'of said screw, thereby allowing the governor to work easier, and to control the motion of the cut-oft' plates n n quicker.

Having thus described our invention, what we claim, and desire to secure by Letters Patent, i's- 1. The movable plates or partitions un', arranged between and in contact with the main valve c and cut-off valve C, substantially as described.

2. The screw J and spindle 7L, together with the wheels k m o and the yoke p, arrangement for disengaging the plates n n from the action of the governor, substantially as described.

Iirwitness whereof we have hereunto set our hands and seals. IRVING M. SCOTT, [L s] t WM. ROBERTS ECKART. [L s] Witnesses G. W. M. SMITH,

GEO. H. STRONG. 

